If the 6-digit number '56x322' is exactly divisible by 18, what is the least value of the digit 'x'?

Answer: A. 0

Divisibility by 18: For a number to be divisible by 18, it must be divisible by both 2 and 9.
Divisibility by 2: The number 56x322 ends in 2, which is even, so it is always divisible by 2.
Divisibility by 9: The sum of the digits must be divisible by 9.
Finding x: For (18+x) to be divisible by 9, must be 0 or 9.
Conclusion: The question asks for the least value, therefore x=0.

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